OFL feature:OFL (Original File Length) is a tool that puts information about the orignal file's length in the bitstream. A decoder that is aware of such OFL information can analyze it and then decode the bitstream having the same starting point and length as the original file (any codec delay or flushing at the end will be removed)."-ofl" is the relevant switch.

VBR encoding:the encoder can now produce bitstreams encoded with variable bitrate. Therefore five modes are provided that can be invoked with the "-m"-switch."-m 1..5" (where "1" represents highest quality and "5" lowest average bitrate).Note: When encoding in VBR mode, "-br 0" must be used. CBR encoding is applied by using "-m 0" and the desired bitrate, e.g. "-br 128000" for 128kbit/s

Sorry for necromancing this thread, but that high quality switch of the encoder doesn't seem to work at all. I've tried it with the normal command line, but the two modes 0 and 1 give exactly the same output. Does anyone have the same problem or maybe even a solution for it?